Malicious PDF — malware analysis report

Static analysis result for SHA-256 9646f2cc69d09f29…

MALICIOUS

PDF

86.3 KB Created: 2021-09-20 09:36:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5ee6b708ba2b13085d4147da2006f9be SHA-1: dc4c7562133e571e4a9a8961317a4d2fda95b83e SHA-256: 9646f2cc69d09f29133e008f7c2468d54a7e6f370a79ea8e7eb15fb21744b114
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm designed to direct users to various external websites, many of which are hosted on compromised or disposable domains. The ML classifier strongly indicates malicious intent, and the presence of numerous links suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210909_052825.pdf In PDF document text
    • https://basundharamart.com/userfiles/file/73672984939.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/81928460079.pdfIn PDF document text
    • https://wigs4less.net/nbloom/fckuploads/file/61681194532.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/me64369o7mmpln67v4agff1gf5/69941714368.pdfIn PDF document text
    • http://spokoino.ru/i/upload/files/vapesutojipagokexopone.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-9-1/20210901084523765164.pdfIn PDF document text
    • http://24cvety.ru/upload/files/bukepusozetotud.pdfIn PDF document text
    • http://www.espace-hotelier.com/ckfinder/userfiles/files/78070618140.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/47636580551.pdfIn PDF document text
    • http://mega-treid.com/userfiles/files/66046079780.pdfIn PDF document text
    • https://kuni.ro/app/webroot/files/userfiles/files/99604835655.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea30e0fed7---91038094998.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/bf05418470cd6c5625fb6a94d58d1a18/xoduwadadegizigikawidil.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109201248354825.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/fidenusisibabunemupi.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/68268796390.pdfIn PDF document text
    • http://saxonrt.hu/img/userfiles/files/73376039234.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/tekiwawari.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/wazizosofikoj.pdfIn PDF document text
    • https://vanrun-it.nl/userfiles/files/66820131534.pdfIn PDF document text
    • http://stisk.com/file/81511294142.pdfIn PDF document text
    • http://precisao.net/files/files/5485322224.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/70491146714.pdfIn PDF document text
    • https://ostrichpharmaceuticals.com/userfiles/file/vepotagagujuguvarogijo.pdfIn PDF document text
    • http://fabriziocar.it/userfiles/files/89072850363.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=crazy+rich+asians+full+movie+free+123moviesPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA28 11220 bytes
SHA-256: 1e975454e2788e445a6634c2bcf15aabdcded61cf4382332115c82d4f5dcac62
font_01_sfnt_off00010472.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10472 18164 bytes
SHA-256: b747fa3487f1f924eb23326263c0e9d29dcc912c65d3be6d48f5bed781a8be2b
font_02_sfnt_off0001337a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1337A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1